DNS delegation of cgi-yahoo.com updated: May 23, 2013 11:42:35 AM
Delegation
step
query
auth
servers
1
cgi-yahoo.com.
.
(f,i,c,g,m,j,d,e,h,l,k,a,b).root-servers.net.
2
cgi-yahoo.com.
com.
(b,m,c,g,a,j,k,e,d,l,i,h,f).gtld-servers.net.
3
cgi-yahoo.com.
cgi-yahoo.com.
(ns2,ns3,ns7,ns1,ns5).yahoo.com.
We pick f.root-servers.net, one of the 13 root servers (1), and ask it about cgi-yahoo.com and learn that com is delegated to 13 name servers (2), so we ask b.gtld-servers.net where we learn that cgi-yahoo.com is delegated to five name servers, including ns2.yahoo.com (3), so we ask that one and get the following answer:
Cgi-yahoo.com is a domain controlled by five domain name servers at yahoo.com. All five of them are on different IP networks. Incoming mail for cgi-yahoo.com is handled by one mail server at .. We are missing the IP:s of one server: .. Cgi-yahoo.com has two IP numbers (68.180.206.184, 98.139.102.145). Both are on different IP networks.
The five name servers ns1, ns2, ns3, ns4 and ns5.yahoo.com together
Three quarter of the several thousand of domains that use name server group 1 point to the two IP numbers 68.180.206.184 and 98.139.102.145 together, hereafter referred to as "IP group 1", (example: yahooooo.net, a1yahoodiscountparts.com and yahoophonesex.com ). Worth noting is that all of the host names that point to IP group 1 use name server group 1.
The mail server. Only
There are several thousand of domains that only use the mail server ..
